Funds are requested to renew core support for 4 core modules. I. Tissue Culture. This laboratory provides modern facilities for the culture of a variety of ocular cells used in different research projects. Five primary and 11 secondary users base important aspects of their research on this laboratory. Core support is requested for a supervisor and basic supplies. II. Histopathology. This important laboratory provides all facilities for tissue processing for light microscopy. It is heavily utilized with 10 primary and 11 secondary users. Core support is requested for a supervisor and basic supplies. III. Ultrastructure (EM). This laboratory provides all equipment and support for scanning and transmission electron microscopy. It is used to full capacity by 5 primary and 17 secondary users. Core support is requested for a supervisor and basic supplies. IV. Vivarium. This modern facility accommodates primates, rodents, rabbits and cats and provides for sterile surgery and special procedures such as necropsy, electroretinography, echography and fundus photography. The vivarium is essential to our entire basic science research effort with 11 primary and 4 secondary users. Core support is requested for a supervisor, a senior vivarium technician and basic supplies.